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How do I migrate a model out of one django app and into a new one?
I have a django app with four models in it. I realize now that one of these models should be in a separate app. I do have south installed for migrations, but I don't think this is something it can handle automatically. How can I migrate one of the models out of the old app into a new one?
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Why return NotImplemented instead of raising NotImplementedError
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It's because __lt__() and related comparison methods are quite commonly used indirectly in list sorts and such. Sometimes the algorithm will choose to try another way or pick a default winner. Raising an exception would break...
What are the differences between the threading and multiprocessing modules?
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What Giulio Franco says is true for multithreading vs. multiprocessing in general.
However, Python* has an added issue: There's a Global Interpreter Lock that prevents two threads in the same process from running Python code at the same time. This means that if yo...
Can “list_display” in a Django ModelAdmin display attributes of ForeignKey fields?
...follow
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edited Jul 25 '14 at 16:10
Denilson Sá Maia
38.5k2828 gold badges9898 silver badges107107 bronze badges
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warning about too many open figures
In a script where I create many figures with fix, ax = plt.subplots(...) , I get the warning RuntimeWarning: More than 20 figures have been opened. Figures created through the pyplot interface (matplotlib.pyplot.figure) are retained until explicitly closed and may consume too much memory.
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How to uninstall the “Microsoft Advertising SDK” Visual Studio extension?
... don't need, but this one won't allow me. if I hover the (enabled!) button it says in a tooltip:
7 Answers
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Does MongoDB's $in clause guarantee order
...o let's say that you were matching on the values of _id in your documents with an array that is going to be passed in to the $in as [ 4, 2, 8 ].
Approach using Aggregate
var list = [ 4, 2, 8 ];
db.collection.aggregate([
// Match the selected documents by "_id"
{ "$match": {
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Calling a function of a module by using its name (a string)
What is the best way to go about calling a function given a string with the function's name in a Python program. For example, let's say that I have a module foo , and I have a string whose content is "bar" . What is the best way to call foo.bar() ?
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How to add a 'or' condition in #ifdef
How can I add a 'or' condition in #ifdef ?
3 Answers
3
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C# operator overload for `+=`?
...or the Garbage collection and memory management, which is a potential security hole in CLR strong typed world.
Nevertheless, let's see what exactly an operator is. According to the famous Jeffrey Richter's book, each programming language has its own operators list, which are compiled in a special m...